Diphenhydramine Hydrochloride

greater than or equal to 100 mg/mL at 70.7 °F (NTP, 1992)

>43.8 [ug/mL] (The mean of the results at pH 7.4)

Breast Feeding; Lactation; Milk, Human; Antihistamines

FDA approved drugs -> Active ingredient

FDA approved drugs -> Active ingredient

Warning

H302 (99.1%): Harmful if swallowed [Warning Acute toxicity, oral]

P264, P270, P301+P317, P330, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 221 reports by companies from 7 notifications to the ECHA C&L Inventory.

Danger

H302: Harmful if swallowed [Warning Acute toxicity, oral]

SYMPTOMS: Symptoms of exposure to this compound may include photosensitivity, hypotension, headache, hemolytic anemia, dizziness, disturbed coordination, nervousness, tremor, insomnia, blurred vision, tinnitus, epigastric distress, nausea, vomiting, diarrhea, constipation and tightness of the chest. Other symptoms may include anaphylactic shock, fatigue, confusion, restlessness, euphoria, diplopia, urinary frequency, drowsiness, urticaria, drug rash, excessive perspiration, chills, dryness of the mouth, nose and throat, palpitations, tachycardia, extrasystoles, thrombocytopenia, agranulocytosis, sedation, excitation, irritability, paresthesia, acute labyrinthitis, neuritis convulsions, anorexia, difficult urination, urinary retention, early menses, thickening of bronchial secretions, wheezing and nasal stuffiness. Other symptoms may include inability to concentrate, muscular weakness, nightmares, difficulty in micturition, elation, depression, hyperpyrexia, muscle twitching lassitude, tingling, heaviness, and weakness of hands. Overdosage reactions may include atropine-like symptoms, dry mouth, fixed and dilated pupils, flushing, gastrointestinal symptoms, central nervous system depression to stimulation, hallucinations, convulsions and death.

Acute Tox. 4 (99.1%)

Acute toxicity (Oral) - Category 4

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SMALL SPILLS AND LEAKAGE: If you spill this chemical, you should dampen the solid spill material with water, then transfer the dampened material to a suitable container. Use absorbent paper dampened with water to pick up any remaining material. Seal your contaminated clothing and the absorbent paper in a vapor-tight plastic bag for eventual disposal. Wash all contaminated surfaces with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with an organic vapor/acid gas cartridge (specific for organic vapors, HCl, acid gas and SO2) with a dust/mist filter. (NTP, 1992)

There is no specific antidote for diphenhydramine toxicity, but the anticholinergic syndrome has been treated with physostigmine for severe delirium or tachycardia. Benzodiazepines may be administered to decrease the likelihood of psychosis, agitation, and seizures in patients who are prone to these symptoms.

Diphenhydramine Hydrochloride

TR-355: Toxicology and Carcinogenesis Studies of Diphenhydramine Hydrochloride (CASRN 147-24-0) in F344/N Rats and B6C3F1 Mice (Feed Studies) (1989 )

10/03/88

Equivocal Evidence

Equivocal Evidence

No Evidence

Drug Induced Liver Injury Rank (DILIrank 2.0)

Diphenhydramine hydrochloride

vNo-DILI-concern

0

No match

DOI:10.1016/j.drudis.2016.02.015

Diphenhydramine

Pharmaceutical

Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

Hepatic and renal Route of Elimination: Little, if any, is excreted unchanged in the urine; most appears as the degradation products of metabolic transformation in the liver, which are almost completely excreted within 24 hours. Half Life: 1-4 hours

ALLERGY DYEFREE

Histamine-1 Receptor Antagonist [EPC]; Histamine H1 Receptor Antagonists [MoA]

DIPHENHYDRAMINE HCI

Histamine-1 Receptor Antagonist [EPC]; Histamine H1 Receptor Antagonists [MoA]

DIPHENHYDRAMINE HCL

Histamine-1 Receptor Antagonist [EPC]; Histamine H1 Receptor Antagonists [MoA]

Drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. They act on any part of the nervous system and on every type of nerve fiber. In contact with a nerve trunk, these anesthetics can cause both sensory and motor paralysis in the innervated area. Their action is completely reversible. (From Gilman AG, et. al., Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed) Nearly all local anesthetics act by reducing the tendency of voltage-dependent sodium channels to activate.

Drugs used to prevent NAUSEA or VOMITING.

Drugs used to induce SLEEP, prevent SLEEPLESSNESS, or treat SLEEP INITIATION AND MAINTENANCE DISORDERS.

Drugs that selectively bind to but do not activate histamine H1 receptors, thereby blocking the actions of endogenous histamine. Included here are the classical antihistaminics that antagonize or prevent the action of histamine mainly in immediate hypersensitivity. They act in the bronchi, capillaries, and some other smooth muscles, and are used to prevent or allay motion sickness, seasonal rhinitis, and allergic dermatitis and to induce somnolence. The effects of blocking central nervous system H1 receptors are not as well understood.

Drugs used to induce drowsiness or sleep or to reduce psychological excitement or anxiety.

Agents that are used to treat allergic reactions. Most of these drugs act by preventing the release of inflammatory mediators or inhibiting the actions of released mediators on their target cells. (From AMA Drug Evaluations Annual, 1994, p475)